(1) Field of the Invention
The present invention relates to a semiconductor module and a manufacturing method thereof. This semiconductor module is obtained as follows: a semiconductor chip requiring a heatsinking property and a peripheral circuit component having the heatsinking property, each mounted on a substrate, are sealed with a resin as one package.
(2) Description of the Related Art
Generally, it is very important to improve a heatsinking property in regard to heat generated upon operation of a semiconductor chip. In order to improve the heatsinking property, a material having good thermal conductivity is used for reducing an adverse influence of the heat generated from the semiconductor chip. A product including a substrate and a package each made of metal has a good heatsinking property. However, a semiconductor module, wherein a semiconductor chip or a semiconductor package and a surface mount component are mounted on a single substrate, has a limitation in configuration because of an increase in cost of materials for constituent elements. A resin substrate or a ceramic substrate to be used for achieving cost reduction is inferior in heatsinking property to a metal substrate.
In order to effectively exert a heatsinking property, it is necessary to bring a heat generating part into close contact with a metal plate and, then, to form circuit components around the heat generating part. Otherwise, it is impossible to obtain a predetermined heatsinking property.
For example, JP2003-347444A (hereinafter, referred to as “conventional example 1”) discloses a semiconductor module releasing heat generated from a semiconductor chip out of a metal case to thereby suppress a temperature of the semiconductor chip within an operating temperature range. Further, JP2002-334811A (hereinafter, referred to as “conventional example 2”) discloses a technique for bringing a semiconductor chip generating heat into close contact with a metal plate.
However, the technique in the conventional example 1 has a disadvantage that a semiconductor module to be obtained is very expensive and a method for manufacturing the semiconductor module becomes complicated. On the other hand, according to the technique in the conventional example 2, a semiconductor chip generating heat is bonded to a metal plate; thus, a semiconductor module with high heatsinking property can be obtained at low cost. However, such a semiconductor chip must be joined to plural peripheral circuit components; therefore, a layout for joining between chip components of a circuit and the semiconductor chip becomes important. Consequently, there arise problems that a long conductor to be used herein inhibits achievement in predetermined property (particularly, high-frequency property), and intersection of conductors leads to restraint in a manufacturing method of a semiconductor module.